Alternating-current switch.



F. W. SMITH & L. LARSEN. ALTERNATING CURRENT SWITCH. APPLICATION FILED MAY 25, 1907.

906,3 1 7. Patented Dec. 8, 1908.

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INVENTQR3 milk 6 W (warn/W 6520a; ATi iEY F. W. SMITH & L. LARSEN. ALTERNATIN G CURRENT SWITCH. APPLICATION FILED MAY 25, 1907.

906,31 '7. Patented Dec. 8, 1908.

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P. W. SMITH & L, LARSEN. ALTERNATING CURRENT SWITCH. APPLICATION FILED MAY 25, 1907.

Patented Dec. 8, 1908 3 SHEETS-SHEET 3 INVENTORS 504% q) c/M G WM FRANK w. SMITH AND LOUIS LARSEN, or NEW YORK, N. -Y.

ALTERNATING-CUBRENT SWITCH.

Specification of Letters Patent.

Patented Dec. 8, 1908.

Application flied lay 26, 1907. Serial No. 875,592.

To all whom it may concern:

Be it known that we, FRANK W. SMITH, and LoUIs LARSEN, citizens of the United States, residing at New York, in the county of New York and State of New York, have invented a certain new and useful Improvement in Alternating-Current Switches, of which the following is a specification.

The invention relates to an electro magnet energized by an alternating current to control mechanism, such as a switch or switches, without producing chatterin or other noises at the contacts, through vibration of the magnet core due to alternations in the energizing current.

The invention consists broadly in the com bination with an electro, magnet, ofa movable core therein, a device to be actuated, such as a circuit closer, transmitting mechanism for' operating said device by said core, andmeans interposed in said transmitting mechanism for thereafter permitting the core to be freelyvibrated by current alternations in the magnet coil, without imparting said motion to said actuated device; also in the construction of the apparatus hereinafter described as embodying our said invention and as more particularly pointed out in the claims.

In the accompanying drawings Figure 1 is a vertical section of the apparatus on the line a: x of Fig. 2'. Fig. 2 is a side elevation and Fig. 3 is a top view, the spring contact stop being removed.

Similar numbers of reference indicate like parts.

1 is the supportin plate, usually of slate.

Secured thereto by olts 2 passing through suitable lugs are two parallel cast iron frames 3, connected by the transverse bolts 4 and receiving between them the rectan lar frame 5 of laminated iron. Disposed within the frames 3, 5, is the electro magnet 6, which is held firmly in position by means of the upper set screws 7 and lower set screws 8 passing through lugs on the frames 3. The magnet core 9 is made of laminations and is rectangular in cross section. It is clamped between two brass guide bars 10 and 11, which at their lower ends are secured to the block 12 against which the lower extremity of said core bears. The upper ends of the guide bars receive between them and are respectively secured to two'lu s 13, 14, which are formed integral with an depend downwardly from the circular plate 15.

In the upper and lower members of frames 3 and 5 .are openings in which the core 9 with its guide bars 10, 11, freely slides; and bolted to the upper side of the 11 per members and to the lower side of the ower members of frames 3 are fixed guide plates 16, having recesses to receive the said sliding guide bars 10 and 11. The object of the fixed guide plates 16 and the guide bars 10 and 11 is to insure the placing, of the'core symmetrically with respect to its inclosing frame and its movement in a right line.

To the under side of. the upper plate 15 is secured a washer 17 of leather or other elastic material. On the upper side of said plate are two brackets 18, '19, respectively carrying metal rollers 20, 21.

Passing through the supporting plate 1 and secured by nuts on its rear side is a pin 22. Freely turning on said pin is a sleeve 23, fast on which is an oifset 24, carrying a pin 25 threaded at its extremity. On sai pm is a cylindrical metal block 26 bearing on the ofiset 24, a metal plate 27 having a projecting portion 28 curled over to form a loop, in which loop a circuit terminal may be soldered or otherwise secured, and finally washers'and nuts 29. Between the block 26 and late 27 are inserted the ends of the bent eaf springs 30, 31, after which the nuts 29 are set up on the pin 25, thus clamping said s rings between said block 26 and plate 27.

he extremities of the springs 30, 31 are preferably bent over as shown, and form flattened contact faces.

Secured to the supporting plate by nuts on its rear side is a pin 32, carr 'ng a standard 33, which receives a carbon b ock 34, secured in place by a threaded bolt 35. The standard 33 is suitably inclined so that the end face of spring 30 may make contact with one side of it as shown in Fig. 1. Secured in like manner to late 1 by a pin 36 is a standard 37, to whic is bolted a carbon block 38, so dis osed that the end face of spring 31 may ma 0 contact with one side of it. Also secured on the sleeve 23 is a forked lever 39. The lower arm 40 of said lever has its edge rounded as shown at a and so placed as that the roller 21 carried by core 9 makes contact with said ed e, when the core is in its lowest position as s own in Fig. 1. The upper arm 41 has its edge elongated and substantiall straight between the points I), c, and witii this edge the roller 21 makes contact when the core 9 rises. Su ported in like manner on the back plate 1, ut on the opposite side of the vertical pathway of the core is a sleeve 42, ,carrying contact springs 43, 44, adapted to make contact respectively with carbon blocks 45, 46, and also a forked lever 47. The construction of these parts is exactly the same as that of the corresponding parts already described.

The straight edge d, e, of the upper arm 48 of lever 47 faces the straight edge b, c, of the 11 per arm 41 of lever 39, and the curved e ge f of the lower arm 49 of lever 47 is opposite. to the curved edge a of the lower arm 40 of lever 39. The rollers 20 and 21, therefore, bear simultaneously on the curved edges a, f, when the core 9 is in its lowest position, and upon the straight edges 1), c, and d, a, when said core is in 1ts raised position.

Supported on the back late 1, directly above the core 9 is a brac et 50, through which loosely passes a vertical rod 51, carryingat its lower end .a block 52, having on its under side a dovetailed recess receiving a sto 53 of india rubber, or other elastic mate-v ria .Interposed between said block 52 and a shoulder on bracket 50 is a helical spring 54, which normally holds the block 52 in lowest position, the, rod 51 being retained by the nut 54 on said-rod above the bracket.

The 0 eration of the ap aratus is as follows: en circuit is bro en through the ma' et coil the parts are in the position shown in Fig. 1. The springs 30, 44, then bear against the contact blocks 34, 45, and circuit may proceed from a terminal A, which may be connected to loop on projection 28 in any suitable way, through spring'30 to contact block 34 and so to another circuit terminal B, connected in any suitable way to said block. Similarly on the other side of the apparatus, circuit may proceed from the terminal 0, through sprin 44 to contact block 45, and so to termina I). When the electro magnet is energized by an alternating current, the core 9 is rapidly lifted. In ascending the rollers 20, 21, meet and pass between the edges 1;, c, and d, c, of the upper arms 41, 48, of the levers 39, 47, and would rise'above them, but is prevented by the elastic stop 53, with which a projection 55 on the plate 15 now comes in contact. The actionof the rollers 20, 21, on the edges 1), c, and d, c of the leverarms 41, 48, is first to swing the arms 39, 47, thus 'moving the.

s rings 30, 44, out of contact with the carbon b ocks 34, 45, and bring the s rings 31, 43, into contact with the carbon locks 38, 46, thus establishing circuit to terminals E and F connected to said blocks. The core now falls back to. a-- osition of equilibrium, the

rollers 20, 21 still bearing on the edges 6,0, and d, e, which stand vertical and substantially parallel. Inasmuch as the current which energizes the electro magnet is alternating, the core will not remain motionless in its equilibrated position, but will vibrate rapidly up and down. This movement of the core, however, is not transmittedto the springs 31 43, because as already stated, the

rollers lie between the vertical parallel edges d, e, b, c, and move. with the core 11 and down alonggsaid edges. Hence said r0 ers impart no vi ratcry motion to the levers 39, 47, and hence the springs 31, 43, rest quietly against carbon blocks 38, 46, without chattering. When circuit is broken to the electro magnet, the core falls, and the rollers 20 and 21 passing between the edges a, f,of levers 39, 47, again swing said levers into the position shown in Fig. 1. The shock of the descent is reduced by the elastic washer 17 which meets the guide plates 16.

Our present apparatus, as shown in the drawings, is arranged as a'double two-way switch. We may omit one of the vibrating levers 39 or 47 and associated contact blocks, and use'it as a single two-way switch. We may omitthe springs 31 and 43 and use it as a double one-way switch, and by omitting in addition one of the vibrating levers 39 or 47 we may use it as a single one Way switch.

As has already been ointed out, the guide bars 10 and 11 and ed guide plates 16 serve not merely to insure the movement of the core in a right line, butalso its symmetrical placing wlth respect to the frame. If means for accomplishing the last named result were not present and the vertical axis of the core were not coincident with the vertical axis of the opening in the. frame, the air gaps on opposite sides of the core would be of different widths, resultingin the practical shortcircuiting of the lines of force across the narrowest gap and consequent impairment of the lifting power of the magnet and chattering. The guide bars and guide plates thus insure air gaps of equal widths on both sides. of the core.

We claim:

1. In combination with an electro magnet, a core movable in a ri ht line, a circuit closer, and a ivoted b' urcated lever controllin said circuit closer, one of the arms of sai lever having a straight elongated edge; said core being constructed and arranged on the energizing of said electro ma net to meet said edge and thereby move sai lever to cause said circuit closer to close circuit, and simultaneously to carry said edge into a position substantially parallel to the line of movement of said core.

2. In combination with an electro magnet, a core movable in a right line, two circuit closers on opposite sides of said line, pivoted bifurcated levers respectively controllin said circuit closers, one of the arms of eac of said levers having a straight elon ated edge; the said core being constructe and arranged on the energizing of said electro ma et to meet said edges and thereby move sai levers to cause said circuit closers to 0 erate and simultaneously to carry said edges into a position substantially parallel I to the line of -'movement of said core.

3. In combination with an electro magnet, an inclosing frame of magnetic material, a core within said magnet longitudinally movable in openings in said frame, two circuit closing arms, a vibrating support therefor, a bifurcated lever actuating said support and actuated by contact of said core with one or the other of its bifurcations to bring one or the other of said circuit clos ing arms into operating position 4. In combination with an alternating current electro magnet, an inclosing frame of magnetic material, a longitudinally movable core within said magnet and means for guiding said core in a right line, and for maintaining equal air gaps on the opposite sides of said core and between said core and said magnet.

5. In combination with an alternating current electro magnet, an inclosing frame of magnetic material, a longitudinally movable core Within said magnet, guide plates on said magnet having recesses, and guide bars on said core entering said recesses; whereby said core is guided in a right line and equal 'air gaps maintained on opposite sides of said core and between sai I core and said magnet.

In testimony whereof we have affixed our signatures in presence of two witnesses.

FRANK W. SMITH. LOUIS LARSEN. Witnesses:

GERTRUDE T. PORTER, H. I. Snma. 

